海湾泥 碱渣和粉煤灰作为园林种植基质的氮素生理类群及生化作用研究

海湾泥、碱渣和粉煤灰是天津滨海地区大量存在的固体废弃物,通过前期室内配比筛选、盆栽试验、田间试验表明其混合基质可以用于园林绿化,并在防护林建设中获得成功.以滨海盐土、客土绿地为对照,对通过脱盐、培肥、种植毛白杨、刺槐、洋白蜡、金银木、紫花苜蓿等园林植物后基质的氨化细菌、好气性自身固氮菌、硝化细菌、反硝化细菌、纤维素分解菌等土壤氮素生理类群的数量进行了研究,同时对呼吸作用、氨化作用强度以及二者与土壤微生物数量、理化性质进行了相关性分析.结果表明,基质的氮素生理类群数量高于或与客土绿地相当,明显高于滨海盐土.呼吸作用高于客土绿地和滨海盐土,氨化作用强度与客土绿地相当,说明混合基质的氮素转化、有机物质的矿化能力以及基质整体的代谢水平好于客土绿地.土壤呼吸作用强度与土壤盐分呈极显著负相关,与细菌数量呈显著正相关.氨化作用强度与全氮、全磷、有机质含量、细菌和真菌数量呈极显著正相关,与放线菌呈显著正相关,与速效钾、盐分呈显著负相关.

Nitrogen Physiological Communities and Biochemical Activities of Planting Mixture Mixed with Brackish Dredged Sediment, Caustic Sludge and Coal Ash

There were great quantity of solid wastes -caustic sludge, coal ash, and dredged sediment in Tianjin coastal area. Previous research has showed that the mixture mixed with these trashes could be used to landscape and became successful in afforestation through combination proportions screens in pot and field experiments. Compared with coastal solonchak and foreign soil, the nitrogen physiological communities of ammonifying bacteria, aerobic nitrogen-fixing bacteria, nitrifying bacteria, denitrifying bacteria and cellulose-decomposing bacteria were studied after the artificial soil was desalinated, ameliorated and planted Populus tomentosa Carr, Robiniapseudoacacia Linn,Fraxinus penn- sylvanica ar.toumeyiehd,Loniccra macckii. Maxim and Medicago sativa L.. Also the intensity of respiration, ammonification and their correlation with the amount of microorganisms, physical and chemical properties were analyzed. The results showed that the CFU of ammonifying bacteria etc. in the mixture was more or equal to foreign soil, and markedly more than that in coastal solonchak. The respiration of the mixed soil was the highest among three soil samples, with ammonification equal to foreign soil. These indicated the nitrogen translation, organic matters mineralization and holistic metabolism of this artificial soil were better than those of foreign soil. Respiration intensity had a very significantly negative correlation with soil salt and significantly positive correlation with the number of bacteria. There existed very significantly positive correlations between ammonification intensity with the content of total nitrogen, total phosphate and organic matters, bacteria quantity, while there was a remarkably positive correlation between ammonification intensity with actinomyces, and a remarkably negative correlation with salt.